The persons who contributed their knowledge to create this course were:
Vera Rubin
(July 23, 1928 – December 25, 2016) An American astronomer who pioneered work on galaxy rotation rates. By studying galactic rotation curves, she uncovered the discrepancy between galaxies' predicted and observed angular motion. Her work provided evidence for the existence of dark matter. These results were later confirmed over subsequent decades.
Henrietta Swan Leavitt
(July 4, 1868 – December 12, 1921) An American astronomer. Her discovery of how to effectively measure vast distances to remote galaxies led to a shift in the understanding of the nature of the universe. A graduate of Radcliffe College, she worked at the Harvard College Observatory as a human computer, tasked with measuring photographic plates to catalog the positions and brightness of stars. This work led her to discover the relation between the luminosity and the period of Cepheid variables. Leavitt's discovery gave astronomers the first standard candle to measure the distance to other galaxies.